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Why is there a beeping sound from TV when SKY card is inserted? Solder a 100nF capacitor between links J72 and J80 behind the card holder.

Why do I get no decoder messages when receiver is hot? Microcontroller or Decoder fault or bad decoder board connector.

The PSU is OK so why will it not light up? 12MHz crystal faulty (May also make it stay in standby)

The PSU is OK but it's stuck in standby 12MHz crystal faulty Cracked track next to tuner lugs.

Is there any way to change the UHF channel? I can see nothing on the back which would afford this adjustment.

If you read the instructions you will find the following details for adjusting the modulator: (these are copied from the GRD300 instructions, but should be the same).

1) Put the receiver in standby.

2) Press and hold [STORE] for about six seconds, until the display changes to 'Cxx' - where 'xx' is the current channel number.

3) Use [P+] and [P-] (or the number keys) to select the output channel you require.

4) Press [STORE] to memorise the setting.

How can I disable the internal decoder to watch MTV2 and VH1 ?

You can use a switch to disconnect one wire of C45, the 1uF capacitor next to the PTV111.

Why is the sound "scratchy"? 8.000MHz crystal faulty

Secret Codes

"Minerva SAT5000", "Matsui RD600" and GRD100.

Pin number: 2580 Astra reset code: 1937 Service mode PIN: 1807 To access Service mode select Main Menu then (4) Installation then Astra reset and press 1807 to get the service screen. DO NOT MESS with these settings!

Notes: VG (Video Gain) must be set according to which tuner module is fitted. If it's set too high you'll get bright, streaky, grainy pictures. If it's too low you'll get intermittent scrambling or no decoder messages.

GRD300 to reset memory: Select Main Menu Press 2 (Install) Press 5 (not shown on screen) Press 2486 You get the option to reset the memory. It takes about 3 minutes and resets only the first 64 channels.

Can I get extra channels? The maximum is 250. You can buy a 250 channel memory chip from SatCure for the GRD150. Place diode 1N4148 in position D15 and D20 (8 positions in a row) This tells the micro "you are a 250" Remove memory chip IC10 (2586) put 24C16 EEprom in position IC11 - NOT IN THE RECENTLY VACATED IC10 position!! This gives 250 chans - DO AN ASTRA RESET. At this point you have 250 chans and can name about 200 - much better.

Remove blue twisted pair of wires by scart sockets. What have we done? - added a video output buffer and an audio-out signal to the scart. I now have a D100 decoder connected to my 250 channel twin LNB early GRD150.

From: Andrew Jardine <a.r.jardine@swansea.ac.uk>

GRD280/Maspro ST9

Why do I get poor pictures? (looks like weak signal) Check the video gain setting and video bandwidth setting.

Can I get more channels? Yes! In the secret service menu, increase the NC setting to 150. This will give the maximum of 300 channels.

Can I get more timer settings? Yes! In the secret service menu, increase the NT setting to 008. This will give the maximum of 8 timer settings.

Can I get more channel names? Yes! In the secret service menu, increase the NN setting to 090. This will give 180 channel names.

Can I alter the video gain? Yes! In the secret service menu, change the VG setting to 032 as a compromise for both Astra and Eutelsat. For Astra only, set NN between 043 and 046. For ET1 only, set NN between 020 and 030.

Can I alter the audio volume? Yes! In the secret service menu, change the AG setting (normally 026). This affects the setting in the main menu.

Can I change the RF modulator sound output from PAL-I to PAL-G ? Yes! In the secret service menu, change the MOD setting from 001 to 000.

Can I *really* screw things up so my receiver will NEVER work again? Yes! In the secret service menu, change ANY setting which is not mentioned above OR change more than one setting at a time without testing the receiver. I guarantee that your receiver will never work again.

1. WRITE DOWN the existing parameters so you can put them back to normal. 2. NEVER change more than ONE parameter at a time and CHECK EVERY CHANNEL after you make such a change.

The memory is limited so if you allocate memory for 300 channels, you won't have enough left to name them all. Trying to do so will cause ... let's say "interesting effects"!

GRD300

Why is the vacuum fluorescent display dim/dead? Usually because one or more of the 10uF electrolytics on the display panel has died. Replace them all and check for poor solder joints as well. Note that all vacuum fluorescent display tubes have a "burn" mark. During manufacture, a tiny piece of magnesium is ignited inside the tube in order to use up any remaining oxygen after the air has been sucked out.

STR300T/Maspro ST12

You can access a special menu on the receiver by pressing

'MENU'

'2'

'5'

code '1910'

This takes you into the set-up menus.

To change the sound output from PAL I to PAL B/G once you get into this menu, change the MT setting to 000.

Most likely is the 47uF/400v capacitor. If a bridge diode went short it will have damaged this cap. Measure its ESR.

>> Yes correct again. When removed, the capacitor showed signs of leakage and >> a replacement cured the fault. >> Many Thanks

DISCLAIMER This information is given in good faith, based on several years of workshop experience involving thousands of repairs. No responsibility will be accepted for any death, damage or injury caused either directly or indirectly by the use of this information. The reader should check the facts himself. It is assumed and stressed that the reader will be familiar with good, safe, electronic workshop practice and will be familiar with all tools, components and terms used. If there is any doubt about the reader's ability to carry out such work competently and safely, the work should be referred to a specialist engineer.